Combined Special Capsular Tension Ring and Toric IOL Implantation for Management of Astigmatism and High Axial Myopia with Cataracts

Effect of capsular tension ring implantation on intraocular lens calculation formula selection for long axial myopia

PURPOSE

The study investigated the effect of capsular tension ring (CTR) implantation on postoperative refractive stability and accuracy of intraocular lens (IOL) formulas for axial length (AL) ≥ 27.0 mm patients.

METHODS

Prospective case series. The eyes of patients underwent phacoemulsification extraction combined with IOL implantation were classified as CTR implantation (A-CTR) and without CTR implantation (B-CON) groups. Refractive outcome and anterior chamber depth (ACD) were recorded at 1 week, 1 month, and 3 months post-operation. Prediction refractive error (PE) and absolute refractive error (AE) of each formula were calculated.

RESULTS

A total of 89 eyes (63 patients) were included and randomized into the CTR (A-CTR) and control groups (B-CON). Comparison of refraction at different postoperative times of the CTR group showed no statistical difference (all P > 0.05). The ACD in the A-CTR group gradually deepened, and that in the B-CON group gradually shallowed (all P > 0.05). The formulas' AE showed statistically significant differences in CTR and CON groups (P < 0.001). The PE of Hill-RBF 2.0 and EVO formulas in the A-CTR group were more hyperopic than that in the B-CON group (all P > 0.05), the other five formulas were more myopic in A-CTR group than that in the B-CON group (all P > 0.05).

CONCLUSION

Patients with 13 mm diameter CTR implantation tended to have stable refraction at 1 week post-surgery and 1 month for those without it. CTR of the 13 mm diameter had no effect on the selection of formulas. Additionally, it is found that Kane and EVO formulas were more accurate for patients with AL ≥ 27.0 mm.

Exploring anterion capsular contraction syndrome in cataract surgery: insights into pathogenesis, clinical course, influencing factors, and intervention approaches

Anterior capsular contraction syndrome (ACCS) is a challenging complication that can occur following phacoemulsification cataract surgery. Characterized by capsular bag wrinkling, intraocular lens (IOL) decentration and tilt, ACCS can have negative effects on visual outcomes and patient satisfaction. This review aims to investigate the pathogenesis, clinical course, influencing factors, and intervention approaches for ACCS after cataract surgery. By understanding the underlying mechanisms and identifying factors that contribute to ACCS, surgeons can enhance their ability to predict and manage this complication. Various intervention strategies are discussed, highlighting their importance in reducing complications and improving surgical outcomes. However, further research is needed to determine optimal prevention and management strategies through long-term follow-up and comparative analyses. Advancements in this field will ultimately lead to improved visual outcomes and optimized cataract surgery for patients.

Insights into the rotational stability of toric intraocular lens implantation: diagnostic approaches, influencing factors and intervention strategies

Toric intraocular lenses (IOLs) have been developed to enhance visual acuity impaired by cataracts and correct corneal astigmatism. However, residual astigmatism caused by postoperative rotation of the toric IOL is an important factor affecting visual quality after implantation. To decrease the rotation of the toric IOL, significant advancements have been made in understanding the characteristics of toric IOL rotation, the factors influencing its postoperative rotation, as well as the development of various measurement techniques and interventions to address this issue. It has been established that factors such as the patient's preoperative refractive status, biological parameters, surgical techniques, postoperative care, and long-term management significantly impact the rotational stability of the toric IOL. Clinicians should adopt a personalized approach that considers these factors to minimize the risk of toric IOL rotation and ensure optimal outcomes for each patient. This article reviews the influence of various factors on toric IOL rotational stability. It discusses new challenges that may be encountered to reduce and intervene with rotation after toric IOL implantation in the foreseeable future.

Comparison of Capsular Tension Ring Implantation before vs. after Toric Intraocular Lens for Rotational Stability

PURPOSE

To compare the effect of implanting the capsular tension ring (CTR) before or after a toric intraocular lens (IOL) on rotational stability in patients with cataract and astigmatism.

METHODS

This is a randomized retrospective study. Patients who underwent phacoemulsification combined with toric IOL implantation due to cataract and astigmatism between February 2018 and October 2019 were enrolled in the study. Group 1 consisted of 53 eyes of 53 patients in whom the CTR was placed into the capsular bag after the implantation of the toric IOL. On the other hand, group 2 consisted of 55 eyes of 55 patients in whom the CTR was placed into the capsular bag before implantation of the toric IOL. The two groups were compared in terms of preoperative and postoperative astigmatism, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and postoperative IOL rotation degree.

RESULTS

There were no significant differences between the two groups related to age and sex (p > 0.05) or the mean preoperative spherical value, UCVA, BCVA, and corneal astigmatism (p > 0.05). Although the mean postoperative residual astigmatism of the first group (- 0.29 ± 0.26) was lower than that of the second (- 0.43 ± 0.31), the difference was not statistically significant (p = 0.16). The mean degree of rotation was 0.75 ± 2.66° in group 1 and 2.90 ± 6.57° in group 2, which was found to be statistically significant (p = 0.02).

CONCLUSION

The implantation of CTR after a toric IOL provides further rotational stability and more effective astigmatic correction.

Postoperative Outcome of Combined Phacovitrectomy in Eyes with Excessive Myopia (>-30 D)

Background

To report the outcomes of phacoemulsification combined with vitrectomy in eyes with extreme myopia (-30 diopters or more). Case Presentation. Three patients with cataract, vitreous opacities, and extreme myopia of more than -30 diopters underwent a combined surgical procedure of cataract extraction combined with vitrectomy. Postoperative refractive correction of the three cases ranged from -1.0 D to -2.5 D spherical equivalent. There was an obvious hyperopic shift of all cases. All patients noted a significant improvement in uncorrected and best-corrected visual acuity from 0.4 to 0.8 in case 1, from CF/70 cm to 1.0 in case 2, and from 0.12 to 0.5 in the right eye and 0.15 to 0.2 in the left eye in case 3. Vitreous floaters disappeared in all cases. No complications were noted during follow-up.

Conclusions

To the best of the authors' knowledge, these represent the first reported clinical cases of combined cataract extraction+vitrectomy surgery in eyes with extreme (>-30 D) myopia. Our results support the notion that phacoemulsification combined with vitrectomy may be a good therapeutic option for cataracts and vitreous floaters in cases with extreme myopia.

Extensive misalignment of plate-haptic rotationally asymmetric multifocal toric intraocular lens

PURPOSE

Plate-haptic rotationally asymmetric multifocal toric intraocular lenses (IOL) (Lentis Comfort Toric) occasionally rotate extensively after surgery. We conducted the current study to investigate the incidence of extensive misalignment of this IOL and its association with clinical parameters.

STUDY DESIGN

Retrospective case series.

SUBJECTS AND METHODS

Data were collected from patients who had undergone phacoemulsification and implantation of a plate-haptic multifocal toric IOL.

RESULTS

Among 332 eyes, extensive misalignment of toric IOLs ≥ 45º occurred in 3.3% (11 eyes). The amount of misalignment in eyes with extensive misalignment was 81.6 ± 22.9º, while in those without extensive misalignment, it was 3.0 ± 2.7º. The eyes with extensive misalignment showed significantly greater axial length (p < 0.001), larger corneal diameter (p = 0.034), and flatter corneas (p = 0.044) than those without extensive misalignment. Repositioning surgery to correct toric IOL misorientation was conducted in 9 eyes between 7 and 28 days after cataract surgery. In 2 eyes, repositioning surgery was carried out twice.

CONCLUSIONS

In majority of cases plate-haptic multifocal toric IOLs showed satisfactory rotational stability, but extensive misalignment ≥ 45º occurred in 3.3% of cases.

Effectiveness of toric IOL and capsular tension ring suturing technique for rotational stability in eyes with long axial length

OBJECTIVE

To evaluate the efficacy of the toric intraocular lens (IOL) and capsular tension ring (CTR) suturing technique in eyes with long axial length (AL) with a high risk of toric IOL rotation.

METHODS

This is a retrospective observational case series. The data files of patients who underwent a one-piece acrylic toric IOL (Tecnis Toric IOL and Acrysof IQ Toric IOL) implantation with the toric IOL and CTR suturing technique for cataract and astigmatism or toric IOL repositioning were analyzed. Inclusion criteria were a regular total corneal astigmatism of ≥ 1.5 D and an AL of ≥ 26.0 mm. Preoperative and postoperative astigmatism, uncorrected distance visual acuity (UDVA), IOL rotation, intraoperative, and postoperative complications were evaluated.

RESULTS

A total of 30 eyes of 29 patients were included in this study. The mean AL was 27.82 ± 1.53 mm (range, 26.08-31.07). UDVA revealed a statistically significant improvement from 0.84 ± 0.20 logMAR preoperatively to 0.04 ± 0.06 logMAR postoperatively (p < 0.001). The mean preoperative corneal astigmatism was 3.08 ± 1.01 D reduced to the postoperative residual astigmatism of 0.59 ± 0.32 D which was found also statistically significant (p < 0.001). Only 2 eyes (6.2%) had postoperative toric IOL rotation of 5° and 10°, respectively. The mean degree of postoperative rotation was 0.50 ± 2.01.

CONCLUSION

This technique provided excellent rotational stability even in eyes with longer AL and did not require additional intervention.

Propensity-matched comparison of postoperative stability and visual outcomes of toric intraocular lens with or without a capsular tension ring and updated meta-analysis

PURPOSE

To assess the contribution of capsular tension ring (CTR) to postoperative stability and visual outcomes of a plate-haptic toric intraocular lens (IOL).

METHODS

This prospective cohort study was performed among patients underwent toric IOL (AT TORBI 709 M) implantation with or without CTR at the Eye and ENT hospital between April 2020 and November 2021. Propensity score matching (PSM) was performed to balance baseline factors. Postoperatively, uncorrected distance visual acuity (UCVA) and residual astigmatism, as well as IOLs' rotation, tilt, and decentration, were analyzed. Grouped multiple linear regression analysis was used to model predictive factors of rotation in each group. Additionally, a meta-analysis of data from 4 publications (284 eyes) and current study was performed to evaluate the effect of CTR co-implantation on toric IOL rotation.

RESULTS

After PSM, 126 eyes from each group were included for further analysis. Postoperatively, UDVA was 0.31 ± 0.38 logMAR and 0.27 ± 0.36 logMAR in the CTR and NCTR groups, respectively (P = 0.441), and residual astigmatism was 0.75 ± 0.52 D and 0.86 ± 0.65 D, respectively (P = 0.139). The rotation of toric IOL was significantly smaller in the CTR group than in the NCTR group (4.63 ± 6.27 vs. 10.93 ± 16.05 degrees, P < 0.001). The regression models of the two groups and the coefficients of LT were significantly different (P < 0.001 and P = 0.001, respectively). Furthermore, the meta-analysis confirmed that CTR co-implantation reduced toric IOL rotation (MD, - 1.59; 95% CI, - 3.10 to - 0.09; P = 0.038).

CONCLUSION

CTR enhances rotational stability of toric IOL by reducing the impact of LT, and CTR co-implantation is recommended in patients with lens thickness (LT) ≥ 4.5 mm, white-to-white (WTW) ≥ 11.6 mm, or high preexisting astigmatism.

How to Manage the Cortex After CTR Insertion

Capsular tension ring (CTR) realizes safe cataract surgery. However, residual cortex removal becomes difficult with CTR. Originally, the flushing technique was developed for intracameral antibiotic administration. Using this technique with larger amounts of solution enables surgeons to 1) deliver antibiotics to the anterior chamber and area behind the intraocular lens, resulting in stable, scheduled antibiotic concentration and 2) entirely irrigate and displace the area, leading to the effective cleansing of residual substances and bacterial pollution. When performing the flushing technique, the residual cortex and debris that were not eliminated by ordinary irrigation and aspiration can be pushed out to the anterior chamber. Applying flushing technique to CTR cases, the residual cortex and debris trapped between the CTR loop and capsular equator is lifted into the anterior chamber and easily removed. If the capsular bag is polluted by bacteria, it may also be lifted to the anterior chamber.

Associations between anterior segment parameters and rotational stability of a plate-haptic toric intraocular lens

PURPOSE

To evaluate the associations between anterior segment parameters and the rotational stability of a plate-haptic toric intraocular lens (IOL).

SETTING

Eye and Ear, Nose, Throat Hospital of Fudan University.

DESIGN

Retrospective case series.

METHODS

Patients who underwent uneventful phacoemulsification and plate-haptic toric IOL (AT TORBI 709M IOL) implantation were included. Preoperative axial length (AL) and anterior segment parameters, including the white-to-white (WTW) distance, anterior chamber depth (ACD), lens thickness (LT), and anterior segment length (ASL; the sum of ACD and LT) were recorded. IOL rotation, residual astigmatism (RAS), and visual acuity were evaluated 1 month postoperatively. The associations between the anterior segment parameters and IOL rotation were evaluated.

RESULTS

A total of 102 eyes of 102 patients were included. The mean AL was 26.43 ± 2.65 mm (range 21.71-34.60 mm). The mean IOL rotation was 4.59 ± 3.18 degrees, and RAS was 0.62 ± 0.39 D postoperatively. No correlation was detected between AL, ACD, or LT and the rotation of the plate-haptic toric IOL (all P > .05). However, its rotation correlated positively with the WTW distance (r = 0.250, P = .011) and ASL (r = 0.214, P = .030). Backward stepwise multiple linear regression revealed that the WTW distance (β = 2.142, P = .014) and ASL (β = 2.060, P = .037) were independent predictors of plate-haptic toric IOL rotation.

CONCLUSIONS

Plate-haptic toric IOLs rotate more in eyes with larger WTW distances and longer ASLs; therefore, toric IOL implantation should be performed with caution in eyes with these characteristics.

Rotational stability of toric intraocular lenses with a newly modified capsular tension ring

PURPOSE

To determine whether a newly modified capsular tension ring (CTR) is effective at preventing toric intraocular lens (TIOL) rotation and misalignment.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Experimental study.

METHODS

Ten human cadaver eyes were used to test the ease or difficulty of TIOL rotation in the capsular bag under 3 experimental conditions: a TIOL alone, a TIOL with a standard CTR, or a TIOL with a newly modified CTR with indentations in a sinusoidal pattern. Scores for the ease of IOL rotation were compared by using the nonparametric Friedman analysis of variance test. In addition, both anterior and posterior Miyake-Apple views were filmed to observe the rotational stability of TIOLs in the capsular bag under the 3 test conditions.

RESULTS

In the ten eyes of five patients, the rotational stability improved with a standard CTR, but further improvement was statistically observed (P < .05) with the newly modified CTR under all test conditions. This was true for both IOLs used (AcrySof and TECNIS toric IOLs), with or without ophthalmic viscosurgical device, and for either clockwise or counterclockwise rotations.

CONCLUSIONS

A newly designed CTR prototype represents a new technology for improving the rotational stability of a TIOL in the capsular bag. Under all test conditions, the prototype performed significantly better than a standard CTR. The results support the use of this new CTR design to improve the accuracy and refractive success of TIOLs.

Effect of capsule tension ring on short-term refractive stabilization and visual performance in trifocal intraocular lens implantation

PURPOSE

To provide refractive stability and increase visual performance with the use of a capsular tension ring in trifocal intraocular lens implantation.

METHODS

This prospective randomized study was conducted in the Yeniyüzyıl university ophthalmology department between February 2018 and September 2019. Eighty-six eyes of 43 patients with visual loss due to uncomplicated cataract in both eyes were randomly divided into two groups, A and B. The eyes in both groups underwent refractive lens exchange with implantation of the same design of trifocal IOL (plate haptic design). In group B, a capsular tension ring was inserted into the capsular bag before trifocal IOL implantation. Both groups were examined at 1day, 1week, 1month, and 3months postoperatively. At 3months after surgery, visual acuity, refractive errors and refractive prediction errors were analyzed and compared between groups A and B.

RESULTS

The postoperative values in group A were spherical equivalent (mean±SD), 0.07±0.79 diopters (D); refractive sphere (mean±SD), 0.43±0.84 diopters (D); uncorrected distance acuity, 0.20±0.04 (logMAR); best-corrected distance acuity, 0±0.02 (logMAR). Group B values were 0.14±0.5 diopters (D), 0.61±0.45 diopters (D), 0.25±0.20 (logMAR), 0.01±0.04 (logMAR), respectively. There was no significant difference between the two groups with respect to the postoperative evaluation.

CONCLUSION

The use of CTR in the implantation of the trifocal intraocular lens had no statistically significant impact on refractive stability.

Effect of capsular tension ring on optical and multifunctional lens position outcomes: a systematic review and a meta-analysis

AIM

To evaluate the effect of capsular tension rings with multifunctional lens position and optical outcomes.

METHODS

We defined multifunctional lens as more than improving vision, but also to restore visual quality. PubMed, EMBASE, Cochrane Library and Scopus were searched for English-language articles published up to November 11, 2020. Randomized controlled trials and comparative prospective clinical trials were selected. Data extraction was completed by independent pairs of reviewers. The risk of bias was evaluated using the Cochrane Collaboration's risk-of-bias tool for RCTs and select items from the Newcastle-Ottawa Scale for comparative prospective clinical trials.

RESULTS

A total of 5 randomized controlled trials and 6 prospective comparative clinical trials were included. One thousand nine hundred and ninety-nine eyes of implantation intraocular lens were evaluated. Capsular tension ring was helpful in un-corrected distance visual acuity (SMD: 0.54, 95% CI = 0.15 to 0.94, p = 0.829) in 1st month. Contrary to 1st month, no show positive effect in 3rd month un-corrected distance visual acuity (SMD: - 0.30, 95% CI = - 0.70 to - 0.10, p = 0.311), corrected distance visual acuity (SMD: 0.02, 95% CI = - 0.78 to 0.81, p < 0.001), sphere (SMD: 0.44, 95% CI = - 0.43 to 1.31, p < 0.001), cylinder (SMD: - 0.12, 95% CI = - 0.36 to 0.13, p = 0.262), and spherical equivalent (SMD: 0.41, 95% CI = 0.13 to 0.69, p = 0.084). Our study also revealed low correlation between capsular tension ring and postoperative optical outcome with un-corrected distance visual acuity (SMD: 0.43, 95% CI = - 0.69 to 1.56, p = 0.001), corrected distance visual acuity (SMD: - 0.11, 95%CI = - 0.43 to 0.20, p = 0.56), sphere (SMD: - 0.26, 95%CI = - 1.18 to 0.66, p = 0.005), cylinder (SMD: 0.10, 95% CI = - 0.39 to 0.59, p = 0.075), spherical equivalent (SMD: 0.22, 95%CI = - 0.10 to 0.54, p = 0.849) in 6th month. The position of intraocular lens co-implantation with capsular tension ring has no significant difference in 1st week with lens decentration (SMD: - 0.34, 95% CI = - 1.19 to 0.51, p = 0.038) and tilt (SMD: - 1.00, 95% CI = - 2.19 to 0.19, p = 0.007), but capsular tension ring is helpful to prevent lens tilt in 1st month (SMD: - 0.67, 95%CI = - 1.08 to 0.27, p = 0.323). In 3rd month, there was no significant difference between two groups in lens rotation (SMD: - 0.51, 95%CI = - 1.71 to 0.69, p < 0.001).

CONCLUSION

The correlation is low between capsular tension ring and postoperative optical outcomes and lens position, based on small numbers of studies in a short range of follow-up.

Can toric IOL rotation be minimized? Toric IOL-Capsular Tension Ring suturing technique and its clinical outcomes

Purpose: In this study, we aimed to evaluate the outcomes of the toric intraocular lens (IOL) and capsular tension ring (CTR) suturing technique in patients with cataract and astigmatism. Methods: Group 1 comprised 37 eyes of 36 patients to whom the CTR-toric IOL complex was co-implanted after the CTR was sutured to the toric IOL haptic. Group 2 comprised 35 eyes of 33 patients in whom the toric IOL and CTR were implanted without suturing. Both groups were compared in terms of preoperative and postoperative astigmatism, best-corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), and IOL rotation. Results: The mean rotation degree was 0.54° ± 2.29° in group 1 and 4.28° ± 8.84° in group 2 (p = .01). While there was no significant difference between the postoperative residual astigmatism and the estimated residual astigmatism in group 1, the postoperative residual astigmatism was statistically higher than the estimated residual astigmatism in group 2 (p = .47 and 0.000, respectively). The mean postoperative UCVA was 0.02 ± 0.04 (logMAR) in group 1 and 0.08 ± 0.13 (logMAR) in group 2 (p = .01). Conclusion: The toric IOL and CTR suturing technique provides excellent rotational stability and astigmatism correction.

Correlation of Intraoperative Optical Coherence Tomography of Crystalline Lens Diameter, Thickness, and Volume with Biometry and Age

PURPOSE

To characterize crystalline lens dimensions derived from in vivo spectral-domain optical coherence tomography (SD-OCT) and identify associations among these parameters, ocular biometry, and age.

METHODS

In this retrospective study, lens thickness (LT), lens diameter (LD), and lens volume (LV) were measured intraoperatively using SD-OCT in 293 eyes undergoing lens surgery. Correlations among LT, LD, LV, age, axial length (AL), and anterior chamber depth (ACD) were analyzed. Multiple regression analysis was performed to determine whether a combination of biometric data could predict LD and LV.

RESULTS

Wide variations were observed in LT (3.6-5.7 mm), LD (7.5-11.9 mm), and LV (119.9-312.4 mm³) of aging eyes. Correlations among the 3 lens dimensions were statistically significant (LV-LT: r = 0.785; P < .001; LV-LD: r = 0.696; P < .001; and LT-LD: r = 0.121; P = .039). With age, the correlation coefficients of LT, LD, and LV were 0.526, 0.326, and 0.573, respectively (P < .001). Although there was significant correlation of AL with LT (r = -0.137; P = .002) and LD (r = 0.268; P < .001), it was not significant with LV (r = 0.084; P = .15). Subgroup analysis revealed that 19.8% of long eyes had LD >1 standard deviation (SD) above and that 5.2% had LD <1 SD below the mean LD.

CONCLUSIONS

Dimensions of the aging lens vary considerably and are most accurately characterized by direct measurement of LT, LD, and LV, rather than making assumptions based on AL. These findings challenge historically proposed relationships between LD and AL and represent a normative dataset of contemporary geometric features of the aging lens, possibly aiding in surgical decision making and future developments in lens surgery.

Comparative evaluation of rotational stability of toric IOLs with four-eyelet vs two-eyelet capsular tension rings in eyes with high myopia

AIM

To compare the rotational stability of Toric intraocular lens (IOLs) implantation combined with four-eyelet or two-eyelet capsular tension rings (CTRs) in eyes with high myopia and cataract.

METHODS

This prospective randomized controlled interventional study included 33 eyes which had preoperative corneal astigmatism ≥1.5 D and ocular axial length ≥25.5 mm. These eyes were randomly divided into two groups to undergo phacoemulsification and toric IOL implantation with either four-eyelet CTR implantation (group A, n=16) or two-eyelet CTR implantation (group B, n=17). Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), phoropter examination results, and toric IOL rotation degrees were tested 6mo after the surgery.

RESULTS

In both groups, the toric IOL was in the capsular sac 6mo after surgery. The difference between the two groups in terms of visual outcome was not found to be statistically significant (P>0.05) at a follow-up of 6mo. The mean residual astigmatism values were 0.56±0.22 D and 0.92±0.24 D in A and B groups, respectively (P<0.001). The mean rotation degree of IOL was 1.00°±0.73° in group A and 3.53°±1.46° in group B (P<0.001).

CONCLUSION

In cataract patients with high myopia and astigmatism, four-eyelet CTR can effectively increase the rotation stability of toric IOLs, achieving the desired goal of correcting corneal astigmatism.

Efficacy of Toric Intraocular Lens and Prevention of Axis Misalignment by Optic Capture in Pediatric Cataract Surgery

PURPOSE

To compare the outcomes of intraocular lens (IOL) implantation using toric (T)-IOL and non-toric (N)-IOL in pediatric cataract patients with astigmatism, and to examine the effect of optic capture (OC) on the axis misalignment (AM) of the T-IOLs.

SETTING

Department of Ophthalmology, Kindai University Hospital, Osaka, Japan.

DESIGN

Interventional, comparative case study.

METHODS

Consecutive pediatric patients implanted with T-IOLs or N-IOLs were retrospectively reviewed. In the T-IOL group, the preoperative and postoperative corrected distance visual acuity (CDVA) and AM were compared in patients with and without OC.

RESULTS

The T-IOL group included 14 eyes of 11 patients, while the N-IOL group included 22 eyes of 15 patients. One year after surgery, the mean ocular cylinder (1.38 ± 0.80 D) was significantly smaller than the average corneal cylinder (3.33 ± 1.24 D) in the T-IOL group (P = .00012, Wilcoxon signed-rank test). The mean preoperative and 1-year postoperative CDVA (logMAR) were 0.57/0.003 (T-IOL) and 0.71/0.09 (N-IOL), respectively. The AM at 1 week and 1 year after surgery was 2.6° ± 3.7° and 4.4° ± 3.1° for the OC group, and 13.3° ± 8.8° and 18.5° ± 14.8°, for the non-OC group, respectively. The AM was significantly smaller in the OC group than that in non-OC group (P = .009, Mann-Whitney U test) at postoperative 1 week.

CONCLUSION

T-IOL implantation is effective in correcting astigmatism in pediatric cataract patients with astigmatism, and the OC technique is likely to achieve lower AM of the T-IOL.

Effect of capsular tension ring implantation on capsular stability after phacoemulsification in patients with weak zonules: a randomized controlled trial. CTR implantation in cataract patients with weak zonules

BACKGROUND

The use of capsular tension ring (CTR) implantation to treat cataract patients with weak zonules is still controversial. The aim of this study was to examine the effects of CTR implantation on capsular stability after phacoemulsification in patients with weak zonules, especially patients who have undergone pars plana vitrectomy (PPV) or those who suffer from severe myopia.

METHODS

A total of 42 patients who underwent phacoemulsification and received an intraocular lens (IOL) were randomized to undergo CTR implantation or not. The control and CTR groups were compared in terms of uncorrected distant visual acuity (UDVA), best corrected distant visual acuity (BCDVA), refractive prediction error, the area of anterior capsulorhexis, and IOL inclination angle. Follow-up visits were conducted postoperatively at 1 day, 1 week, 1 month and 3 months. Subgroup analyses were performed based on PPV and severe myopia.

RESULTS

Surgery significantly improved UDVA and BCDVA to similar extents in CTR and control patients, and refraction prediction error was similar between the two groups at all follow-up times. At 3 months after surgery, the area of anterior capsulorhexis was significantly larger in CTR patients than in controls (p = 0.0199). These differences were also significant between the subgroups of patients with severe myopia. Vertical IOL inclination was less within CTR groups at 3 months after surgery, especially in patients with severe myopia (p = 0.0286). At 1 week postoperatively, the proportion of individuals whose posterior lens capsule that had completely adhered to the posterior IOL surface was significantly higher among CTR patients (p = 0.023). No serious surgical complications were observed.

CONCLUSION

CTR implantation can benefit cataract patients with weak zonules by maintaining the shape of the capsular bag, reducing capsule shrinkage and stabilizing IOL inclination.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-INR-17011217 , date of registration April 22, 2017, prospectively registered.

Agreement between anterior segment parameters obtained by a new ultrasound biomicroscopy and a swept-source fourier-domain anterior segment optical coherence tomography

Purpose: To evaluate the agreement between anew UBM and an SS-OCT. Methods: The scans of the right eye of each volunteer were obtained using the two devices. Data were fitted and recorded including: central corneal thickness (CCT), aqueous depth (AQD) (the distance from endothelium to lens), angle-to-angle distance (ATA), lens thickness (LT), diameter of the lens in the horizontal direction (LDia^angle: distance between the sharp angles on both sides of the lens, LDia^arc: distance between the vertex of the circular arcs on both sides of the lens), anterior and posterior corneal radius (Rf and Rb). Results: 25 eyes were included in this study. It could be seen that the differences in CCT, LDia^angle, Rf measured by the two instruments were not statistically significant. Bland-Altman analysis plots of CCT, LDia^angle and Rf showed mean differences of 0.2 µm, 0.01mm and 0.0mm for the 2 devices, respectively. Conclusion: The values of CCT, LDia^angle and Rf obtained via two instruments were not clinically interchangeable and the AQD, ATA, LT, and Rb have poor agreement affected by accommodation. We can estimate the real lens diameter by subtracting 0.61 ± 0.43mm when the lens diameter can only be simulated with SS-OCT.

[Comparative evaluation of positional stability of the «capsular bag + intraocular lens» complex in patients with lens subluxation]

Prevention of decentration and dislocation of the "capsular bag + intraocular lens" (IOL) complex in the late postoperative period is an actual problem of surgical treatment of patients with pronounced lens subluxation.

PURPOSE

To conduct a comparative clinical study of positional stability of the "capsular bag + IOL" complex in the late postoperative period after application of a combined technique of capsular bag fixation in patients with subluxation of the lens.

MATERIAL AND METHODS

Phacoemulsification (PE) with in-the-bag IOL implantation and postoperative observation was performed in 213 patients (234 eyes) with cataract and pronounced lens subluxation. The 1^st group consisting of 138 patients (153 eyes) underwent capsular bag fixation of the combined technique with simultaneous use of 4 modified iris-retractors and one or two capsular tension rings (CTRs). The 2^nd group included 75 patients (81 eyes) who in the course of PE had their capsular bag fixed beyond the edge of capsulorhexis with only 4 modified iris-retractors. Preoperative state of the lens and the evaluation of the frequency and degree of decentration of the «capsular bag + IOL» complex in the postoperative period were performed using data acquired with ultrasound biomicroscopy (UBM).

RESULTS

Significant (more than 1 mm according to UBM) IOL's optic decentration was observed in the 1^st group after applying the combined capsular bag fixation technique in 12 (7.8%) cases, and in the 2^nd group after isolated use of modified iris-retractors in 48 (59.3%) cases.

CONCLUSION

The use of the combined capsular bag fixation technique not only improves the conditions for carrying out PE with in-the-bag IOL implantation in patients with pronounced lens subluxation, but also contributes to a substantial (an average of 8 times) reduction in the incidence of significant decentration of the «capsular bag + IOL» complex in the late postoperative period.

Effects of capsular tension ring on surgical outcomes of premium intraocular lens in patients with suspected zonular weakness

Purpose

To assess the influence of capsular tension ring (CTR) on surgical outcomes of toric and multifocal intraocular lenses (IOLs) in eyes at high risk of zonular instability.

Methods

Fifty-five eyes of 43 patients who had undergone phacoemulsification and IOL implantation were included in the analysis. They had some risk of zonular weakness, such as pseudoexfoliation, shallow anterior chamber, high myopia, and phacodonesis, or were judged to have unstable zonules during surgery. Toric IOL was implanted in 9 eyes with CTR and 22 eyes without CTR, while multifocal IOL was used in 9 eyes with CTR and 15 eyes without CTR. Manifest refraction, refractive astigmatism, visual acuity, and degree of IOL decentration and tilt measured using swept-source anterior segment optical coherence tomography were analyzed. Axis misalignment of toric IOLs were also evaluated.

Results

In toric IOLs, co-implantation of CTR significantly reduced decentration and axis misalignment of IOL, resulting in better uncorrected and corrected visual acuity after surgery. In multifocal IOLs, combined use of CTR significantly prevented IOL tilt, leading to better intermediate visual acuity. Spherical equivalent and residual astigmatism were not significantly affected by the use of CTR.

Conclusions

CTR reduces decentration and axis misalignment of toric IOL and tilt of multifocal IOL, achieving improvement of postoperative visual function in eyes with suspected zonular instability.

Rotation of a toric intraocular lens with and without capsular tension ring: data from a multicenter non-inferiority randomized clinical trial (RCT)

BACKGROUND

Evaluation of clinical outcome in cohorts with versus without simultaneous implantation of a capsular tension ring (CTR) and a toric lens (Tecnis Toric). Main parameter was rotation referring - in contrast to misalignment - to the IOL axis change from immediately after implantation to the final postoperative position.

METHODS

Lens position was measured at baseline with the patient still in recumbent position, postoperative rotation was calculated by software. Postoperative evaluation included measurement three months after surgery or prior to an indicated revision surgery. Explorative re-evaluation of the underlying RCT's intent-to-treat population was performed for the entire sample and stratified for cohorts by 95% confidence intervals for binary endpoints' incidences (primary endpoint: absolute postoperative rotation ≤5 degrees; secondary endpoints: absolute deviation between achieved cylinder and target cylinder ≤0.5 dpt, postoperative corrected distance visual acuity (CDVA) ≥ 0.8). Data exploration was based on medians and quartiles.

SETTING

Outpatient study sites.

DESIGN

Re-evaluation based on data from a multicenter non-inferiority randomized clinical trial (RCT).

RESULTS

Sub cohorts (without CTR 89, with CTR 90 patients) did not present clinically relevant differences in preoperative characteristics: revision surgery was performed in 7 cases (3 without and 4 with CTR). Primary endpoint incidences for the total sample, without and with CTR were 90%/89%/90%; cylinder endpoint incidences were 46%/45%/46% and CDVA endpoint incidences 90%/92%/88%. Median absolute rotations were 1.74°/1.79°/1.72°, median absolute cylinder deviations 0.55/0.52/0.55 dpt and median visual acuity 1.0/1.0/1.0.

CONCLUSION

No clinically relevant differences between CTR subgroups were found; a satisfying three months rotational stability was achieved.

TRIAL REGISTRATION

The trial was registered retrospectively in the trial registry DRKS, trial registration number DRKS00015316 , date of registration 27. August 2018.

Comparative evaluation of rotational stability and visual outcome of toric intraocular lenses with and without a capsular tension ring

Purpose:

To evaluate the rotational stability of toric intraocular lens (IOL) when co-implanted with a capsular tension ring (CTR) as compared to that of a toric IOL without a CTR.

Methods:

This was a prospective randomized clinical trial performed in a tertiary care centre in India. Fifty adult human eyes with visually significant cataract and regular corneal astigmatism ≥1.5D divided into two groups of 25 eyes each, A and B by simple randomization. Eyes with corneal pathology, lens subluxation, and a specular endothelial cell count <2000/mm² were excluded from the study. The eyes in both the groups underwent standard phacoemulsification and were implanted with a toric IOL. In Group A, a CTR was put in the bag before IOL implantation. The groups were called for follow-up on day 1, 1 week, 1 month, and 3 months, postoperatively. The axis of the toric IOL on each visit was measured by slit lamp imaging in retroillumination and analyzed digitally.

Results:

Mean rotation of toric IOL at 3 months postoperatively was 1.85 ± 1.72° in Group A and 4.02 ± 2.04° in Group B. The difference was statistically significant (P = 0.003).

Conclusion:

Coimplantation of a CTR is a safe and effective technique for ensuring better rotational stability of toric IOLs.